Master of Science, The Ohio State University, 2023, Entomology

Bumble bees (Bombus) are essential pollinators for wildflowers and crops worldwide, but many species are currently in decline. Habitat loss and fragmentation are leading factors in these declines. Urbanization is a source of habitat loss and fragmentation; however, robust and abundant bumble bee populations are often found in metropolitan areas. Though prior research has broadly examined bumble bee abundance and diversity in urban areas, little work has focused on individual abundances of different species, which may differ in their relationships with urban land. Furthermore, the potential impacts of urban land on gene flow and other genetic health factors in bumble bees remain largely unknown. The first goal of this research was to evaluate and compare the abundances of three target species—Bombus impatiens Cresson, 1863, B. griseocollis De Geer, 1773, and B. bimaculatus Cresson, 1863—along an agricultural-to-urban gradient in Madison, WI, USA. Bumble bees were collected from 16 sites during the summer of 2019 and 19 sites during the summer of 2020. The second goal was to evaluate genetic differentiation, heterozygosity, allelic richness and colony numbers among populations of these species along the same gradient. Percentage of impervious surface cover was used as a metric for urbanization, and this percentage was measured within both 500 m and 1500 m buffers around each study site to account for both local-scale and landscape-scale effects. Impervious surface cover showed no relationship with abundances of B. impatiens or B. griseocollis, but showed a positive relationship with abundance of B. bimaculatus. Impervious surface cover also showed no relationship with genetic differentiation, allelic richness or colony number for all three species in both years, and no relationship with heterozygosity for any species in 2019. In 2020, heterozygosity was negatively correlated with impervious surface cover for B. impatiens at the 500 m buffer but not the 1500 m buffer. (open full item for complete abstract)

Doctor of Philosophy (PhD), Ohio University, 2022, Biological Sciences (Arts and Sciences)

Bats are the second most numerous mammalian taxon and provide critical human ecosystem services such as pollination and pest control. Globally, they are threatened by multiple factors such as habitat degradation, contamination, and emerging diseases such as white-nose syndrome (WNS). This disease is caused by a fungus, which was introduced from Europe to North America, and has killed millions of bats, with some species showing precipitous declines in abundance. A result of such population decline is the loss of genetic diversity, and hence the loss of adaptive potential. The goal of this dissertation is to use genetic data to further understand the population ecology of two bat species that are differentially affected by white-nose syndrome, the big brown bat, Eptesicus fuscus, and the northern myotis, Myotis septentrionalis. The first species doesn't show symptoms of the disease and is potentially playing a significant role in spreading the pathogen. I estimated the population genetic structure and estimated genetic differentiation among eight states using data from the cytochrome-b gene. I found moderate population structure, suggesting that dispersal and gene flow is occurring mostly within states, but movement across long-distances are possible as suggested by a moderate fixation index. In addition, I inferred population size trends and found that the big brown bat populations are declining, an unexpected result for an abundant species. The second species that I studied was the northern myotis. This species has shown a drastic decline in winter surveys, with declines of about 95%. To investigate recent population size changes, I first assembled the genome using short and long-read data. The final assembly was largely contiguous, composed of 92 fragments, and had a high completeness, with a BUSCO Score of 96.1% of the mammalia orthologs core genes. The genome annotation was very complete as well, with 55075 genes and a BUSCO SCORE of 98.5%. It also indicate (open full item for complete abstract)

Master of Science, The Ohio State University, 2024, Genetic Counseling

Cascade testing for Hereditary Breast and Ovarian Cancer syndrome (HBOC) is central to identifying family members at heightened risk for cancer. Despite the well-documented importance of cascade testing, such as the United States Centers for Disease Control and Prevention and Office of Public Health Genomics naming HBOC a Tier 1 Genomics Application, current data suggest that the uptake of cascade testing remains suboptimal (Fehniger et al., 2013; Menko et al., 2019). There are many cited barriers to family discussion of HBOC and cascade testing, and research suggests that healthcare providers can alleviate certain barriers by providing informational resources to facilitate patient-mediated communication (Chivers Seymour et al., 2010; Srinivasan et al., 2020, Frey et al., 2022). In this survey-based study, 103 individuals with a likely pathogenic or pathogenic variant in BRCA1 or BRCA2 were recruited. We assessed the reactions to and impact of a 2-minute animated video (BRCAShare), in conjunction with a family communication guide, on the intrafamilial sharing of genetic test results. The BRCAShare video, guided by the Health Belief Model (HBM), depicts a hypothetical scenario of a relative's recent diagnosis of HBOC. Surveys assessed three domains from enrollment to post-study: 1) participants' intent to share; 2) perceived susceptibility, seriousness, benefits, or barriers to intrafamilial sharing of results and cascade testing; 3) the impact of family dynamic on sharing. All participants received the electronic family communication guide, while only one randomized group received the BRCAShare video in addition to the communication guide. Those who viewed the video had significantly higher odds of reporting intent to share compared to those who did not, suggesting that a video message is an effective method for increasing family communication about HBOC and cascade testing (p<0.05). Results also suggest that participants who viewed the video perceived sharing to be (open full item for complete abstract)

MS, University of Cincinnati, 2024, Medicine: Genetic Counseling

Objectives Significant gaps exist in the understanding of the presentation of genetic conditions across the lifespan, particularly during the prenatal period. This study aimed to describe the limitations of prenatal phenotyping by detailing the differences between prenatal and postnatal evaluations of neonates with genetic conditions. Methods We conducted a retrospective chart review of neonates with genetic diagnoses who previously received a detailed prenatal phenotype evaluation by fetal ultrasound, MRI, and echocardiogram at the Cincinnati Children's Fetal Care Center (CCFCC) between July 2018 and October 2022. Details of the prenatal and postnatal phenotypes were collected using Human Phenotype Ontology (HPO) terms to compare findings between the time points. Results Between July 2018 and October 2022, there were 85 neonates with genetic diagnoses who were prenatally evaluated in the CCFCC; these patients either received diagnoses prenatally (n=38), postnatally (n=45), or differing diagnoses before and after birth (n=2). The number of HPO terms significantly increased after postnatal evaluation (mean: 8.45) compared to what was identified prenatally at time of referral (mean: 3.45) (p<0.001) and during CCFCC evaluation (mean: 4.41) (p<0.001). There was a significant increase in the number of anomalies noted postnatally in most body systems compared to what was observed prenatally, including the musculoskeletal, nervous, genitourinary, head and neck, and respiratory systems. Conclusions There is a significant increase in phenotypic information in most body systems that becomes available as a fetus grows and after a child is born. Thus, fetuses with anomalies should be evaluated at multiple time points during prenatal life and after birth to ensure comprehensive phenotype information is available, particularly when a genetic etiology is suspected since most genetic testing and interpretation is phenotype driven. Awareness of bod (open full item for complete abstract)

Doctor of Philosophy, The Ohio State University, 2023, Plant Pathology

Phytophthora root and stem rot is one of the top ten most yield-limiting soybean [Glycine max (L.) Merr] diseases in the U.S. and Canada. The causal agent of this disease, Phytophthora sojae (Kaufmann & Gerdemann), is an oomycete (water mold) organism that is often managed by using disease-resistant soybean cultivars containing a single Rps gene to a specific pathotype of the pathogen combined with quantitative disease resistance (QDR). Due to the limitation of the number of effective Rps genes available, as the populations of this pathogen have adapted to these genes, it is a necessity to find new Rps genes and identify perfect markers for QDR genes, which have a smaller effect but can resist all pathotypes of P. sojae, that can be used in the development of modern soybean cultivars. In this dissertation, the main approach for all three chapters is to examine the mechanisms of disease resistance in soybeans towards P. sojae using different forward and reverse genetic approaches. A previous study found more than 100 candidate genes by mapping the expression quantitative disease-resistance loci (eQDRL) from the Conrad × Sloan population. To explore and validate the functions of these genes, a fast neutron (FN) population from the University of Minnesota, derived from soybean cultivar M92-220, with these genes deleted was employed. Thus, the first chapter's first objective was to compare cultivars M92-220 and Conrad at phenotypic and transcriptomic levels for their QDR resistance to determine if the molecular mechanisms associated with the eQDRLs were similar to those previously found in Conrad. Then, the next objective was to explore how the loss of the candidate genes using mutants that were highly susceptible would affect the soybean resistance response following inoculation with P. sojae by examining the three most susceptible FN mutants. Conrad and M92-220 were found to share high levels of QDR in the phenotypic assay as well as having several similar defense-r (open full item for complete abstract)

Master of Science, The Ohio State University, 2023, Genetic Counseling

With the increasing knowledge of genetics and the expansion of targeted therapy options, genetic testing for conditions like Amyotrophic Lateral Sclerosis (ALS) is increasing in demand. Since relatively few ALS clinics are staffed by a genetic counselor, non-genetics neurology providers will need to play key roles in genetic test result interpretation, communication, and implementation into patient care. However, physicians across various fields of practice have communicated a lack of confidence in interpreting and communicating uncertain genetic results, a common result for patients with ALS who undergo genetic testing. This questionnaire-based randomized controlled study was conducted to assess whether a genetics educational module could increase non-genetics neurology providers' understanding of and comfort with uncertain genetic testing results in ALS-associated genes. This anonymous online study-questionnaire assessed each participant's baseline genetics knowledge and comfort with interpreting and communicating genetic testing results. Following this, participants were randomly assigned to either the intervention or control arm. The intervention arm received a comprehensive genetic testing educational module, while the control arm received a condensed version that only covered inheritance patterns. The study questionnaire then re-evaluated each participant's genetics knowledge. The questionnaire also assessed their clinical interpretation and comfort level when presented with a hypothetical case vignette featuring an uncertain genetic testing result in an ALS-associated gene. While the results did not reach statistical significance due to a low number of respondents, certain trends were observed. As compared to control arm participants, intervention arm participants had a greater increase in knowledge after receiving the educational module and were more likely to include certain key implications of the case vignette uncertain result in their written interpret (open full item for complete abstract)

Doctor of Philosophy, Miami University, 2022, Ecology, Evolution and Environmental Biology

Dispersal is an important ecological process that enables the persistence of populations in the environment and reduces both demographic and genetic isolation. In the context of rapid anthropogenic land use/land cover change, understanding how individuals and populations across multiple species respond to changing, heterogeneous landscapes is instrumental in assessing current and future land use/land cover affect species movement. The objective of my dissertation was to assess factors affecting individual movement behavior in multiple habitats and habitat configurations, and then link those individual movement behaviors to patterns of population genetic structure and landscape-scale conductance. My central hypothesis was that intrinsic and extrinsic factors affect the movement, dispersal, and population connectivity of anuran species both individually and in tandem. Therefore, by assessing the interaction of these factors, we can link factors that affect behavior at an individual scale to patterns of connectivity at a broad scale. To test this hypothesis, I conducted a suite of three experiments addressing desiccation tolerance and individual movements of three anuran species at two distinct size classes in multiple habitat combinations. Further, I assessed population genetic structure and landscape conductivity of two anuran species utilizing individual behavioral data to parametrize my conductance models. Both body size and habitat type affected individual movement behavior, though the effects of habitat type, and especially orientation at habitat edges had relatively stronger affects. Parameters based on movement data were informative in landscape-scale models of conductance, though natural and anthropogenic landscape features such as road and river networks were found to strongly affect functional connectivity. Even so, I explicitly linked movement behavior and landscape level patterns of connectivity, and showed that over the same landscape, species specific r (open full item for complete abstract)

Master of Science, The Ohio State University, 2022, Public Health

Understanding which regions of a genome are under selection is critical in order to enable effective responses to rapidly-evolving viruses. The need for such tools has been amplified by the recent COVID-19 pandemic. We apply two different methods of selection identification, a phylogenetic likelihood method and a simulation of the Wright-Fisher Diffusion model, to empirical data for SARS-CoV-2 obtained from the public GISAID repository. Phylogenetic Analysis by Maximum Likelihood (PAML) is an open source program developed by Ziheng Yang in 1997. We utilize PAML to identify sites within the COVID- 19 variant genomes which are experiencing positive selection. PAML uses a standard codon substitution model to compute likelihoods associated with various values of ω, a selection parameter which indicates positive selection if greater than 1. Results from PAML's M0, M3, and M8 models are compared. The M0 model estimates a single value of ω for an entire protein-coding region, while the M3 model estimates the K most likely values of ω within the protein-coding region of interest and associated probabilities, where K is user-specified. The M8 model estimates P (ω > 1) as a point mass and then generates a Beta distribution of probabilities associated with the remaining values of ω where P (ω < 1). We then conduct an alternative analysis using a continuous-time approximation to the Wright-Fisher model. The approximation is a stochastic differential equation (SDE) which describes the frequency of type A alleles over time and contains the selection parameter β. We simulate the model using the Euler Method, record the final allele frequency q, utilize q to estimate the likelihoods associated with various values of β, and then record the MLE of β for each SARS-CoV-2 variant. The results of the two analyses are compared, followed by a discussion of potential implications to the future state of the COVID-19 pandemic.

Doctor of Philosophy, The Ohio State University, 2022, Evolution, Ecology and Organismal Biology

Successful conservation actions require a detailed understanding of how individuals interact with their environment. For many threatened and endangered species, anthropogenic changes to their landscape have created barriers separating formerly connected populations. This isolation can have profound impacts on the long-term viability of these populations and ultimately the conservation status of the species. For example, as populations become more isolated, they may enter the “extinction vortex” where small populations experience high levels of inbreeding and genetic drift depressing demographic rates, driving the population into a positive feedback loop that can lead to a decline in numbers and eventual extinction. However, if barriers to movement are not complete, even infrequent dispersal between populations can counter potential vortex effects by bolstering local population sizes and introducing new genetic material. Determining if populations are connected via dispersal or if they are isolated is a difficult question with no single best approach. For the Federally threatened Eastern Massasauga Rattlesnakes, Sistrurus catenatus, their reclusive, sedentary lifestyle make many field-based methods for generating this information difficult and unreliable without unrealistic investments of time and resources. In my thesis, I used information from DNA single nucleotide polymorphisms (SNPs) from neutral genetic markers to address the following three fundamental questions regarding how S. catenatus move through their landscape in Ohio and how this information can be used to evaluate proposed activities for their conservation: (1) Do snakes in scattered habitat patches across Northeastern Ohio belong to a single connected population, a metapopulation with infrequent dispersal, or isolated populations? I used 1000s of DNA SNPs to reconstruct a pedigree across 86 individuals and showed that no individuals have moved between habitat patches separated by more than a few (open full item for complete abstract)

Doctor of Philosophy, The Ohio State University, 2021, Molecular, Cellular and Developmental Biology

Congenital heart disease (CHD) is the most common birth defect in live births with an estimated incidence of 1%.  Although advancements in surgical care have significantly improved patient outcomes, CHD is still a major contributor to morbidity and mortality. The link between genetics and CHD has been well established following population-based studies and single-gene knockout approaches in animal models. Although a subset of CHD can be attributed to a few key genetic contributors, the genetic underpinnings of most CHD cases remain unresolved.  Therefore, uncovering novel genetic contributors to CHD is of critical importance. Large scale sequencing approaches of patients with CHD have identified numerous potentially damaging genetic variants. However, gene prioritization and experimental validation for the majority of these candidate genes are lacking. Model organism studies, specifically those performed in mice, have been instrumental in uncovering the developmental impact that genetic contributors have on the developing heart. The growing availability of genomic technologies allows us the opportunity to exploit mouse models of CHD as a tools to facilitate gene discovery. We propose that transcriptomic profiles derived from the normal developing heart and animal models of CHD can be used to prioritize candidate genes that contribute to CHD phenotypes in patients and also identify novel genes and molecular pathways critical for heart development. To better understand the genetic contributors of tetralogy of Fallot (TOF), we designed a gene prioritization pipeline that made use of transcriptomic data derived from a highly penetrant mouse model of outflow tract (OFT) malformations and genetic variant information derived from patients with TOF. The common OFT is the anatomical precursor of the aorta, pulmonary artery, and semilunar valves. Disruption of the normal development of the OFT contributes to OFT malformations such as TOF.  We performed bulk RNA-Sequencing o (open full item for complete abstract)

Doctor of Philosophy, Case Western Reserve University, 2020, Epidemiology and Biostatistics

Hypertension (HTN) or elevated blood pressure (BP) affects 1 in 3 adults in the US. Across ethnicities, BP levels have been consistently higher for African Americans (AA) with an earlier onset of HTN. Many studies have investigated racial differences in HTN, especially genetic factors contributing to disease progression. While genome-wide association studies (GWAS) have identified over 900 loci associated with BP variation, these variants together only explain a small portion of the heritability. Several studies have shown that rare variants could explain a portion of the “missing heritability”. Linkage analysis of families is a promising approach for detecting genetic signals because it is insensitive to allelic heterogeneity and facilitates the discovery of missing heritability due to rare variants. This dissertation includes two of the first studies to leverage linkage evidence from family-based studies and search for BP-associated rare variants in trans-ethnic whole genome sequencing (WGS) data. Because only a small amount of GWAS variants fall within linkage regions, combining linkage and association analyses would yield a powerful and robust approach for detecting rare variants. Given the increasing availability of WGS data, efficient approaches are needed to interrogate a large number of genetic variants involved in disease etiology. Although directly searching the whole genome using window-based or gene-based approaches are commonly implemented, these methods may suffer from statistical power lost due to the large number of statistical tests. In contrast, confining to genomic regions with linkage evidence helps to reduce the multiple testing burden. Furthermore, because variant annotation is independent from linkage information, it can be incorporated into rare variant association analysis. By leveraging linkage evidence from European American (EA) families, SLX4 was shown to be associated with pulse pressure in EA. Linkage evidence in AA families led to the (open full item for complete abstract)

Master of Science in Biological Sciences, Youngstown State University, 2019, Department of Biological Sciences and Chemistry

Stenotrophomonas maltophilia Oak Ridge Strain OR02 (S. maltophilia 02), which was isolated from a heavy metal contaminated site in Oak Ridge, TN, grows in the presences of toxic levels of heavy metals, including selenite. Selenium exists in four different valences as selenate (+6), selenite (+4), elemental selenium (0) and selenide (-2). Selenate (SeO42-) and selenite (SeO32-) are soluble, uncolored forms of selenium and elemental selenium forms an insoluble red precipitate. Microbes that use selenium, import it into the cell as selenite, reduce it to selenide and incorporate it into selenocysteine. When environmental selenite concentrations are higher than required, some bacteria reduce it to insoluble elemental selenium and methylate it to form volatile methyl selenide. When S. maltophilia 02 is growing in the presence of 0.5 mM sodium selenite, it produces an insoluble red precipitate and a stale garlic odor, which are presumably elemental selenium and methyl selenide, respectively. A subtractive hybridization technique was used in an attempt to identify genes that are expressed in response to high concentrations of selenite. S. maltophilia 02 was grown to early log phase and exposed to 0.5 mM selenite. After two hours of selenite exposure, RNA was extracted from untreated and treated cultures. The RNA was converted to double stranded cDNA and cut with the four-base cutter, restriction endonuclease, Sau3AI. After ligating linkers to the digested cDNA, it was amplified by PCR. The PCR reaction on the untreated cDNA was labeled with dCTP and dUTP biotin. The PCR reaction on the treated cDNA did not contain biotin labeled nucleotides. PCR products from both reactions were mixed, heated at 98°C to denature the DNA and allowed to hybridize at 68°C for 24 hours. The hybridization mixture was added to streptavidin magnetic beads and exposed to a magnetic stand to remove the cDNA from RNA that was present under both the treated and untreated conditions. The remaining cDN (open full item for complete abstract)

Master of Science, The Ohio State University, 2019, Genetic Counseling

Although the clinical importance of cascade testing in families with hereditary cancer syndromes is well documented, complicated discussions can arise when genetic information is shared and subsequent discussions among relatives are often complicated. Novel communication aids should be considered to assist aid in these conversations. To investigate one possible method, we evaluated the theoretical impact of receiving unsolicited information about genetic testing performed in one's family through a video that could be shared via text or social media. Participants (N=399) viewed a video describing a relative's recent BRCA+ diagnosis and the potential impact on themselves. They also completed a survey with questions regarding thoughts on the message, hypothetical willingness to act on results, and other measured variables. The electronic survey instrument was built using the Health Belief Model, which postulates that an individual is more likely to engage in a behavior if they perceive greater risk in their severity and susceptibility, greater benefits than barriers to engagement in the behavior, self-efficacy, and a cue to action. This framework was used to measure participants' willingness to undergo genetic testing, seek out a genetic counselor, discuss genetic testing with their doctor, and talk to family members about their family history of cancer. Characteristics shown to impact intent to take action in these categories included intolerance of uncertainty, having a close family history of cancer, and greater family dynamics (ps < .05). A majority of participants (75.95%, N=300) would undergo genetic testing if it cost $100 or less. Additionally, a majority of participants (70%, N=281) were willing to meet with a healthcare professional to discuss genetic testing. Understanding potential reactions to receiving unsolicited genetic information is the first step in investigating novel communication aids in cascade testing.

Master of Science, The Ohio State University, 2019, Genetic Counseling

Background: Sudden arrhythmia death syndrome (SADS) conditions, including ion channelopathies and cardiomyopathies, are genetic conditions that cause sudden cardiac death (SCD). Genetic testing in SADS conditions is imperative as there is a significant amount of phenotypic variability in these conditions. Current management options, including medications and implantable cardioverter defibrillators (ICDs), do not effectively treat all SADS conditions and may even have significant negative psychosocial implications. Genetic treatment technologies, such as gene therapy and gene editing, may be utilized in the future as a treatment option in the care of individuals with SADS conditions. No studies have been done to assess the SADS community's familiarity with and likelihood to utilize genetic treatment technologies as a treatment option. Methods: Members of the SADS Foundation email directory with a personal or family history of a SADS condition were available to participate in a cross-sectional online survey. The survey focused on the familiarity of and likelihood to utilize ICDs, gene therapy, medications, and gene editing. To explore the factors that influence the likelihood of utilizing the various treatment options, state and trait anxiety, genetic knowledge, and perceived risks were measured. Results: A total of 109 completed surveys were obtained from individuals with a personal diagnosis of a SADS condition and individuals with a family member with a SADS condition. A majority of participants reported being familiar with ICDs (n=102, 93.6%) and medications (n=97, 89%), but unfamiliar with gene therapy (n=81, 74.3%) and gene editing (n=89, 81.7%) as a treatment option for SADS conditions. A majority of individuals reported being likely to utilize ICDs (n=86, 78.9%), medications (n=99, 90.8%), and gene editing (n=65, 59.6%), while fewer were likely to utilize gene therapy (n=55, 50.5%). Participants who were unfamiliar with gene therapy were unlike (open full item for complete abstract)

Master of Science in Biomedical Sciences (MSBS), University of Toledo, 2017, Biomedical Sciences (Bioinformatics and Proteomics/Genomics)

Genetic variations are the heritable changes in DNA caused by mutation and can be present in both coding and non-coding region of the DNA. They provide great resources for the evolution of an organism in response to environmental and biological changes. Analysis of these variants (such as Single Nucleotide Polymorphism (SNPs), Indels, and other structural variants like Copy Number Variations (CNV)) thus, have a wide range of potential applications. These include identification of causative variants and the genes for genetic diseases, personalized genomics, population and evolutionary genetics, and forensic biology. This study represents two such applications of human variant analysis (particularly the analysis of SNPs and Indels). In the first chapter, SNPs were analyzed to understand the correlation between recombination rate and genetic diversity in the human genome, using a computational modeling program. A simulated human population was used to study the effect of various population level factors such as natural selective forces, the type of mutations, etc., on this correlation. In the second chapter, Next Generation Sequencing (in this case Whole Exome Sequencing) data and associated computational variant analysis tools and software were used to analyze both SNPs and Indels in the human genomes to find a lead candidate genetic variant responsible for Inherited Retinal Dystrophy in a family.

Master of Science, The Ohio State University, 2017, Genetic Counseling

Introduction: Genetic testing for cardiovascular disease (CVD) is a powerful tool that enables clinicians to identify genetic forms of CVD and predict the risk for CVD in at-risk family members. Cardiovascular genetic testing has advanced over the past ten years, but these advancements have posed new challenges mainly in the field of variant classification. To address these challenges, the American College of Medical Genetics and Genomics (ACMG) published guidelines for the interpretation of sequence variant interpretation in 2015. Goal: The goal of this study was to determine what impact the ACMG guidelines have on variant classification in clinical cardiovascular genetics. Methods: We performed a retrospective chart review to identify patients who underwent clinical genetic testing and were found to have a variant identified in a gene associated with CVD. For each variant, systematic evidence review was performed by collecting information from both public and private variant databases and PubMed. We applied the ACMG guidelines to each variant for classification, which were compared to classifications provided on patients' genetic test reports. Results: This study identified 223 unique variants in 237 patients. Eighty (36%) of the variants resulted in classifications that differed from their clinical reports. Twenty-seven (34%) of these reclassifications were determined to be clinically significant. In total, these variant classifications affected 101 patients in a single clinical setting. For 39 patients (39% of 101), these reclassifications would result in changes in medical management recommendations for their at-risk relatives. Conclusion: Application of the ACMG guidelines resulted in a change of classification for approximately one-third of the variants in this study. Clinical genetic counselors can have a more active role in the process of variant classification. It is important for variant classifications to be updated over time (open full item for complete abstract)

Doctor of Philosophy, The Ohio State University, 2002, Graduate School

Doctor of Philosophy (PhD), Ohio University, 2016, Biological Sciences (Arts and Sciences)

The Diamondback Terrapin (Malaclmeys terrapin) is a turtle found in brackish water habitats along the Gulf and Atlantic coastlines of the North American continent. Historically, terrapins have had a complex relationship with humans, including over- harvesting, habitat loss and degradation, and translocations. Furthermore, ecological and molecular studies of terrapins yield conflicting results with respect to terrapin population biology. Resolving these conflicts is integral to understanding how past human activities have influenced the contemporary distribution and abundance of terrapin genetic diversity. In Chapter 1, I surveyed the terrapin literature and identified incongruences between ecological and molecular studies. I finish Chapter 1 with recommendations for future molecular and ecological terrapin studies. In Chapter 2, I demarcated metapopulation structure and quantified gene flow between populations in Chesapeake Bay. I detected four populations with weak structure, high admixture, high genetic diversity, and genetic signatures of anthropogenic translocation. In Chapter 3, I quantified the effective population sizes of the Chesapeake Bay populations, with both ecological and molecular approaches. Using mark-recapture, Bayesian model testing, and approximate Bayesian computation, I recovered incongruent results among methods. I then used mark-recapture data to rule out spurious molecular estimates, finding that coalescent models more accurately estimate effective population size in Chesapeake Bay. In Chapter 4, I used a range-wide dataset to locate major terrapin populations, quantified historical and contemporary gene flow, and tested for bottlenecks. I used Bayesian model testing and discriminant analysis of principal components (DAPC) as well as historical terrapin literature to show the terrapin's phylogeographic structure was best explained by anthropogenic translocation events in the early 1900's. In Chapter 5, I revisited a classic terrapin phylogeo (open full item for complete abstract)

Master of Science in Botany, Miami University, 2016, Biology

Wild crop relatives serve as a natural genetic reservoir for crop improvement as they may harbor alleles that aid in disease resistance and environmental adaptability. One major threat to the reservoir of genetic diversity in wild populations is habitat fragmentation which may isolate populations and reduce genetic admixture across agricultural lands. Carica papaya is a dioecious early successional species native to Central America and is potentially threatened by habitat fragmentation. It can be found growing along roadsides, abandoned fields, and secondary lowland forests. Morphological and genetic diversity was measured for wild papaya in regions of Costa Rica and Nicaragua. Connectivity in the landscape was measured using Circuitscape in ArcMap10.3. Wild papaya is morphologically consistent in certain traits, in particular, its small, yellow, seedy fruits, and vegetative characters tend to vary more than reproductive characters. The genetic health of wild papaya was moderate, but diversity is partitioned among regions as a consequence of inbreeding. We have evidence that wild papaya is susceptible to the detrimental effects of habitat fragmentation which inhibits gene flow and promotes inbreeding. Conservation efforts should focus on areas of high connectivity and selecting natural individuals for a living germplasm line.

Doctor of Philosophy, Miami University, 2015, Biology

Species conservation is an enormously complex task, which includes identification of phenomena that affect the loss, maintenance, and restoration of biodiversity and advocate for sustaining evolutionary processes that promote all levels of biological organization. Endangered species conservation requires a comprehensive approach to evaluate the conservation status of a given species, develop optimal recovery plans, and establish quantitative recovery criteria, in order to remove the necessity of protection. In my dissertation, I demonstrate such a comprehensive approach for evaluating the conservation status of two imperiled freshwater mussel species: Cumberlandia monodonta and Popenaias popeii, and providing guidance for development of species recovery plans. I characterized novel microsatellite markers for the species in order to assess population genetic diversity and structure (Chapter 1 and 3). I assessed fine-scale population structure of C. monodonta and used ecological and genetic simulations to investigate the effects of future climate change on distributional shifts in suitable habitats and population genetic connectivity (Chapter 2). I also investigated evolutionary history and genetic structure of P. popeii and used long-term mark-and-recapture monitoring to determine population dynamics (Chapter 4 and 5). I used demographic and population genetic information acquired from the previous chapters to develop recovery strategies for these species (Chapter 6). Using a large number of polymorphic microsatellite markers for both species, I revealed that climate change during the mid-to-late-Pleistocene likely shaped current distribution and genetic structure in both species. Current genetic structure of C. monodonta is likely a consequence of connectivity of suitable habitat; however, future climate change will likely reduce connectivity across populations. Climate change during the mid-to-late Pleistocene caused regional and local population structures of P. p (open full item for complete abstract)